I’m in the process of wiring an attic roof fan. The fan is in the middle of the attic and the power source is at the end of the attic. The attic is open with insulation between the joists and plywood down the center of the floor.
Attic does not have trusses.
What’s the best / easiest (code compliant ) way to run the romex to the fan?
Thank You
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Replies
Run a 2x3 down the bottom truss chords and staple the RX to the side of the 2x3, then follow the side of the truss up to the fan.
Your objective is not to have the wire where you will be stepping on, crawling on or otherwise crushing it.
It is safer to use screws to attach the 2x3 (predrill the holes in the 2x3). Less chance of cracking the drywall below than hammering in nails.
I second that answer.
Attic does not have trusses...should have mentioned that in original post.
Same thing. You still want to protect the cable by using a running board.
Oops,
Forgot to mention the attic does not have trusses...just roof rafters.
Why not run the Power up to the bottom of the rafters and staple it there? Its out of the way and I doubt there is any worry about someone hanging something from it in an unfinished attic.
Acces to and height of the space matters
Per the NEC:
If the attic space has access via stairs or permenate ladder (fold down stairs?) it effects how the wire must be protected.
If there IS a stair/ladder the wires must be protected.
If there is NOT a ladder or stairs, and the wire is >6' from the attic scuttle hole opening, no protection is needed. If no stairs/ladder and < 6' to the enternace the wire must be protected as descrived above in previous post or attach to the side of joists/rafters or installed thourgh holes bored through the members. If no stairs/ladder and the space is <3' tall no protection is necessary.
BTW - weather it has trusses or not is not of concequence, however I guess it is a good thing to know for people who are trying to access the situation.
Of course, "protected" is a
Of course, "protected" is a vague term with lots of interpretations and footnotes. By some interpretations if the cable is simply kicked back in the "crotch" of the framing that's sufficient for a horizontal attic run at right angles to the rafters. No one could possibly step on the cable in that location.
I think protected is defined in the NEC.
And the generally accepted method is to nail a 2x? across the framing members and run the romex along side that. Either that or attached to the side of the joist or run through holes bored through the joists. I've learned about this protecting attic wiring thing via inspection rejection and went over the book with the inspector. That was a few years back though.
I think the idea is that they don't want a HO putting storage boxes, etc directly on wiring.
Do you know if it is acceptable to run the wire under the attic floor joists assuming that there is strapping attached to the bottom of the attic floor joists and the strapping is thicker than the romex? If so can the romex just lie loose on the ceiling? I had read somewhere that this is ok, after all if one were installing a new ceiling fixture in a finished room wouldn't this be the way the wiring would be done?
A lot depends on the inspector.
If the strapping is thick enough....
maybe staple to the side of it? It may be safer not to, as the danger here comes more from below than above. My concern would be that someone may want to put a hook into the ceiling for a hanging plant or something, and hit the Romex.
You can drill thru the middle of the joists to run Romex, but if you get too close to the bottom, you have to put those steel plates on to prevent nails reaching it. I think it's like a couple inches, somebody who knows the NEC off the top of their head will probably supply the correct number.
-- J.S.